Ether ketones



United States Patent 3,316,305 ETHER KETONES Arno Calm, Pearl River, N.Y., and Allan H. Gilbert, West Englewood, N .J., assignors to Lever Brothers Company, New York, N.Y., a corporation of Maine No Drawing. Filed July 26, 1962, Ser. No. 212,706 8 Claims. (Cl. 260-594) This invention relates to novel chemical compounds and more particularly to ether-ketones having desirable fragrances and to methods for the preparation of such compounds.

In the manufacture of cleansing compositions containing detergents, it has been found necessary to incorporate materials having pleasant fragrances in order to mask undesirable odors in the detergent composition thereby to increase consumer acceptance of the product. The well-known fragrant materials of the ester class such as benzyl acetate and benzyl propionate are examples of such additives. However, since most detergent formulations contain alkali, perfumery materials such as the aforementioned esters are decomposed by hydrolysis either during storage or during use in aqueous solutions.

A further problem which has arisen in the use of perfumery materials in cleansing compositions concerns the presence of bleaching ingredients. The latter materials tend to oxidize perfumery additives and it has been found that the perfumes are decomposed upon storage in the presence of many bleaching ingredients.

It is an object of this invention to synthetically produce perfumery materials having desirable fragrances.

A further object is the production of compounds with desirable odor characteristics which retain their fragrances in the presence of bleaching ingredients and which are stable in alkaline media.

Other objects and advantages of the invention will be apparent from the following description.

It has now been found that the above objects and advantages can be attained by a compound of the formula:

wherein R is a straight or branched-chain alkyl group having at least 4 carbon atoms; R R R R R and R each are radicals selected from the group consisting of hydrogen and straight or branched-chain alkyl groups having from 1 to about 3 carbon atoms with not more than two of the radicals being alkyl; R" is a straighbchain or branchedchain alkyl group having from 1 to about 4 carbon atoms; m, n and p are integers whose sum is greater than 2; the total number of carbon atoms in the molecule being no more than about 20. Preferred compounds are those in which R ranges from 4 to about 12 carbon atoms and the sum of m, n and p is less than 6. Examples of compounds coming within the above formula are the following: S-isobutoxy-pentanone-Z; 5-(2,4-dimethyl-pentoxy)-pentanone- 2; S-(n-pentoxy)-pentanone-2; 2-methyl-6-isobutoxy-hexaanone-3; 4-methyl-S-isobutoxy-pentanone-Z; 6-isobutoxyhexanone-Z; etc.

Each of these materials is endowed with a pleasant fragrance and is suitable for use in a perfume base. The compounds have strong, lasting fragrances and are stable in detergent compositions containing alkali and/or bleaching ingredients. Furthermore, many of the compounds of the invention have a low afiinity for hard surfaces which is advantageous when they are employed in dishwashing CROSS REFEREiiCE HAMMER 3,316,305 Patented Apr. 25, 1967 formulations because of the low residual perfume content which remains on glassware washed with the formulation.

The ether-ketones of the invention may be prepared by various procedures, some of which have a general application while other methods are peculiar to particular compounds. However, any method of preparation known to those skilled in the art may be employed.

In the preparation of S-alkoxy-Z-pentanones, a suitable method has been developed which involves the use of a]pha-acetyl-gamma-butyrolactone as a starting material. The reaction equation is as follows:

H01 CH:CHC OCH: CHaC O(CH1)aCl A detailed description of this method is set forth in Example 4, infra.

Another procedure for preparing some of the etherketones of this invention involves the free-radical addition of aldehydes such as acetaldehyde to allyl ethers:

It is necessary to carry out this reaction under carefully controlled conditions to obtain satisfactory yields. Thus, for optimum results, ditertiary-butyl peroxide should be employed as the free-radical catalyst using glass-lined equipment and a temperature within the range of about ll5l30 C. The allyl ether may contain alkyl substituents of 1-3 carbon atoms attached to the allyl radical to produce ether-ketones having alkyl-substituted methylene radicals, i.e., some of the radicals R are alkyl.

The following examples illustrate the preparation of materials according to the invention. It will be understood, however, that these examples are included merely for purpose of illustration and are not intended to limit the scope of the invention as described herein, unless otherwise specifically indicated.

EXAMPLE 1 15.6 grams of 2,4-dimethylpentyl allyl ether (0.1 mole), 1.5 grams of ditertiary butyl peroxide (0.01 mole) and 13.2 g. of acetaldehyde (0.3 mole) were placed in a glasslined pressure reactor and heated at 115-125 C. for 24 hours. Excess pressure was vented and the contents of the reactor removed and distilled to yield 9.3 g. of 5-(2,4- dimethylpentoxy)-2-pentanone, B. l071l2 C./ 10 mm., n =1.4274. This material retained its fragrance when subjected to Cl and alkali for two weeks at F.

Scent characteristics Odor: lavender, fruity, jasmin. Intensity: strong. Retention: good.

Efiect of temperature-Table 1 below shows the effect temperature on the yield of 5-(2,4-dimethylpentoxy)-2- pentanone. Different catalysts were used in these experiments to obtain approximately equal half-lives at the 75 grams of the dioxolane (0.46 mole) was added to a solution of 10.6 grams (0.46 mole) of sodium in 296 grams (4 moles) of isobutyl alcohol and the mixture refiuxed for 16 hours. 500 ml. of water was added foltemperatures employed. 5 lowed by enough concentrated hydrochloric acid to make TABLE RATIOSOF REACTANTS the solution distinctly acid to litmus paper. The solution was then refluxed for 1 hour after which the product was !2I4 Dimethy1penty1' Acetag Catalyst Temp; Time, Yielm isolated by ether extraction. Distillation gave 57.6 grams i' Ether dehyde hrsi Benefit of -iso-butoxy-2-pentanone, a colorless pleasant smelling oil, B. 9595 C./0.24 mm., n =1.4169. g 28-} 32:38 3: g This compound displayed a fragrance resembling rose 1 3 s 1 85.95 24 0 and lavender. It is chemically stable in soap and deg 2 g} g1 g2 tergent formulations and is well retained by such media.

' Its manner of use in perfumery is illustrated by the folz ggr gg e lowm g formula. 1! Ditertiary butyl peroxide. Rose lavender Efiect of glass-lining in the pressure vesseI.-Table 2 Parts y Weight shows a comparison of two runs carried out in a reactor Lavandifl Oil 400 with and without a glass lining, respectively. 5-is0but0xy-pentan0nc-2 00 TABLE 2.MOLAR RATIOS OF REACTANTS 2,4-dimethyl- Acetal- Ditertiary pentylAllyl dehyde Butyl Peroxide Temp, Time, Lining Yield,

Ether C. hrs. percent 1 3 0.1 115-125 24 None 5 1 a 0.1 115-125 24 Glass 45 EXAMPLE 2 Coumarin 80 65 Eugenol 40 12.8 grams of isobutyl methallyl ether (0.1 mole), 1.5 h 1 th r 50 grams of ditertiary butyl peroxide (0.01 mole) and 13.2 e e atchouh Oll 20 g. of acetaldehyde (0.3 mole) were placed 1n 8. glass-lined Musk ambrette 10 pressure reactor and heated at 115-125" C. for 24 hours. Excess pressure was then vented, the contents of the 70 1000 reactor removed and distilled to yield 7.7 g. of S-isobutoxy- 4-methyl-2-pentanone, B. 79-82.5 C./l0 mm., n This perfume mixture displayed an adequate fragrance 42 2. level when used at 0.8 to 1.0%.

Scent characteristics The compounds 5-(n-pentoxy)-pentanone-2 and 6-isobutoxy-hexanone-Z were prepared by methods similar to 2:2; gfi ggfiggit iigfigi ketomc' 75 those described above. The scent characteristics of the respective compounds are as follows: Retent1on: good.

EXAMPLE 3 33 grams of 3 i b l hl id (Q22 l 45 5-(n-peut0xy)-peutauone-2 6-isobutoxy-l1exauone-2 was refluxed with stirring with 5.8 g. (0.24 mole) of magnesium and a crystal of iodine in 150 ml. of anhydrous celery'nkei kemllicafi g kgg ether. The Grignard product gradually formed over a Intensity-- Equals linalool. Equals lii'mlool. period of 5 /2 hours. 12.8 g. of isobutyronitrile (0.186 Relemionn- Gwd mole) in 20 ml. of ether was then added at the reflux temperature and the mixture refluxed for an additional 1 hours after which it was left overnight. Ice was then The retenflori characteflsfics 0f the compounds were added to decompose the complex, f ll d by 200 1 assessed qualitatively by determining the disappearance of of 50% sulfuric acid. The product was isolated by ether fragrance a perfumers blotter impregnated with the extraction and distilled to give 24.5 g. of 2-methyl-6-isotest P butoxy-hexanone-3, a pleasant smelling colorless oil, B. We clalmi 11441 c at 25 mm =1 42() 1. A compound which has the generic formula:

Scent characteristics )n )m )p Odor: pineapple, ester-like. wherein R is an alkyl group having at least 4 carbon Intensity: stronger than linalool. atoms; R R R R R and R are each radicals se- Retention: good. lected from the group consisting of hydrogen and alkyl groups having from 1 to about 3 carbon atoms with not EXAMPLE 4 more than two of the total R -R radicals being alkyl; R 5'chloro'z-pentanone was P p in 76% Yield from 5 is an alkyl group having from 1 to about four carbon y -g y 0186mm and hydrochloric acidatoms; m, n and p are integers whose sum is greater than grams of this ketone mole) and 62 grams of 2; the total number of carbon atoms in the molecule being ethylene glycol (1 mole) were refluxed in 600 ml. of benno more than about 2 zene conatining 1 gram of p-toluenesulfonic acid using a 2 A compound f h for l Dean-Stark trap to remove the water formed in the reaction. After 6 hours, the benzene solution was washed a)2 2- 2)a s with sodium bicarbonate solution and water, and then distilled to yield 106.4 grams of 5-chloro-2-pentanone di- A compound of the formula oxolane as a colorless oil, B. 6666 C./O.4 mm, (CH CHCH --CH(CH n 1.4478. 7., CHZO (CHZ) aa 5 4. A compound of the formula:

7. A compound of the formula:

(CH CH-CH O(CH -COCH 8. A perfume according to claim 1 in which R is isobutyl, n-pentyl or 2,4-dimethylpentyl.

References Cited by the Examiner UNITED STATES PATENTS Nelles 260594 Geyer et a1. 260-594 Ladd 260-594 Lazier et a1 16794 Fiore et a1, 167---94 OTHER REFERENCES Nerdel et 211.: I. Prakt, Chem. 8, 171-180 (1959).

WITZ, Examiners.

LEON ZITVER, Primary Examiner.

LORRAINE A. WEINBERGER, DANIEL D. HOR- UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,316,365 April 25, 1967 Arno Cahn et a1 It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Column 3, line 57, for "n read n line 74, for "66-66 C./0.4 mm.," read 66-68 C./0.4mm., line 75, for "n read n column 4, line 10, for

"B.9595" read B.94-95 Signed and sealed this 21st day of November 1967 (SEAL) Attest:

EDWARD J. BRENNER Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

1. A COMPOUND WHICH HAS THE GENERIC FORMULA: 